On Sept 13 Sony will livestream the next product launch event directly from the IBC show in Amsterdam. 3 years ago they did launch the A7sII at this event but I do not think yet the new A7sIII camera will be announced there this year. Seems pretty save guess to me that we will finally get the new FX9 FF E-mount 6K camcorder. Plenty of stores listed the camera on their website:
IBC 2019 – SONY will introduce the NEW 6K Full Frame PXW-FX9 camera. It is scheduled to ship December 2019.
This camera can be seen as the new Full Frame, 6K version of the popular PXW-FS7 with a new proprietary AI Autofocus System (Face/Eye detection) as available on SONY flagship DSLR cameras and IBIS.